Depends which OSX version you have for both, I don't know if your hardware supports the last one, but you might need the correct cable, HDMI doesn't do it for me, and if your intel GPU can't, it won't, not an OSX issue.

They are both MacOS issues.

The first one is simply impossible to do on Monterey.

The 4k 144 thing is a software regression (so not a hardware limitation) that still hasn't been fixed: https://discussions.apple.com/thread/253168625

I hate the every year we update model. I never do it for iOS or OSX. Miss snow leopard: selling point: 0 new features.

I don't have a 4k monitor but I have an ultrawide that does 144Hz. The only way I found to use it that way was via SwitchResX.

Does it make a big difference? I heard 60hz freesync would make a bigger difference than high refresh, it looked nice when I had 144hz but aside from me sliding my mouse it didn’t really change anything.

60Hz is absolute minimum, but it's also mostly sufficient.

120-144Hz is a lot nicer though. All animations, scrolling, even just moving the pointer, look and feel smoother and snappier.

Depends on the person, but for me it makes a big difference.